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Mammography information questioned
COPENHAGEN, DENMARK. A large study of the benefits of mammography screening for breast cancer
was carried out in 2001 by the prestigious Cochrane Institute. The study questioned the benefits of
screening and pointed out that screening could be harmful in that it frequently leads to over-diagnosis and
over-treatment. The Cochrane Institute has now released the results of a new study aimed at
determining how fairly the benefits and dangers of mammography are presented on web sites. They
evaluated 13 sites maintained by advocacy groups, 11 maintained by governmental institutions, and 3
maintained by consumer organizations. They found that all the advocacy group sites accepted
sponsorship from industry without restriction. The close relationship can perhaps best be summed up in
this quote from the Canadian Cancer Society, “Partnership with the Canadian Cancer Society can assist
your company in reaching your commercial objectives.”
The researchers found that all the governmental agencies and advocacy groups heavily favoured
screening and significantly downplayed the drawbacks; the consumer health organizations took a much
more balanced view. The advocates particularly highlighted a 30% reduction in the risk of dying from
breast cancer if regular screening takes place. They often failed to mention that this 30% reduction is a
relative reduction and not an absolute reduction. Of course, emphasizing a 30% reduction is much more
impressive that stating that having mammograms may reduce the risk of dying from breast cancer by
0.1% over a 10-year period. The advocates also downplayed the fact that women having regular
mammograms would have a 49% chance of being recalled for a biopsy during a course of 10
mammograms and that mammograms can be painful – so painful in fact that many women refuse a
second one.
The researchers conclude that, “The information material provided by professional advocacy groups and
governmental organizations is information poor and severely biased in favour of screening. Few websites
live up to accepted standards for informed consent such as those stated in the General Medical Council’s
guidelines.”
Jorgensen, KJ and Gotzsche, PC. Presentation on websites of possible benefits and harms from screening for
breast cancer: cross sectional study. British Medical Journal, Vol. 328, January 17, 2004, pp. 148-53
Editor’s comment: It is indeed unfortunate that mammography has such a stranglehold on
breast cancer detection at least in North America and Western Europe. This virtual monopoly and the
enormous industry supported by it is no doubt responsible for the fact that newer, more accurate, less
dangerous, and painless techniques such as thermography, scintimammography, nipple secretion
analysis, and duct imaging are not given a fair trial.
New rapid, painless test for breast cancer
PHILADELPHIA, PENNSYLVANIA. The standard screening for breast cancer involves physical
examination and mammography. Mammography is notoriously unreliable and often results in
unnecessary biopsies and much anxiety. Researchers at the Thomas Jefferson University now report the
preliminary results of a new rapid, accurate, non-invasive, painless breast cancer screening test. The test
involves collecting a very small amount of breast nipple fluid (1 microliter) with an ordinary breast pump
and then analyzing its protein content using the SELDI (surface-enhanced laser desorption/ionization time
of flight-mass spectrometry) technique.
The researchers tested the procedure on 20 women with breast cancer and 13 healthy controls. They
found that the women with breast cancer excreted five proteins that were not excreted, or excreted in
miniscule amounts, by the healthy women. Thus a protein with a molecular mass of 6500 Da was found
in 75 per cent of the women with breast cancer, but not in a single one without. Similarly a protein with a
molecular mass of 15940 Da was found in 80 per cent of the women with breast cancer, but not in any of
the healthy women. The researchers conclude that the new technique may materially aid in detecting
breast cancer in its earliest stages.
Sauter, E.R., et al. Proteomic analysis of nipple aspirate fluid to detect biologic markers of breast cancer.
British Journal of Cancer, Vol. 86, May 6, 2002, pp. 1440-43
Mammography debate rages on
STOCKHOLM, SWEDEN. Swedish researchers have reviewed the results of four mammography-
screening trials carried out in Sweden up to and including 1996. The studies included 129,750 women
who were invited to undergo screening (actual attendance rate was about 80 per cent) and 117,260
controls. The women were followed up for an average 15.8 years from time of entry to the study. During
the follow-up there were a total of 22,398 deaths in the screening group of which 795 (3.5 per cent) were
ascribed to breast cancer. The corresponding numbers for the control group was 20,945 total deaths of
which 847 (4.0 per cent) were ascribed to breast cancer.
A closer examination of the data revealed that the benefits of mammography were limited to women
between the ages of 55 and 69 years at the start of the study. The reduction in breast cancer mortality
ascribed to mammography screening was 24 per cent (29 deaths per 100,000 women years versus 38
deaths per 100,000 women years in the control group) for the ages 55 to 59 years. It rose to 32 per cent
for the age groups 60 to 64 years and 65 to 69 years. No statistically significant benefits were seen
outside the age range of 55 to 69 years.
Dr. Karen Gelmon of the British Columbia Cancer Agency says that, “the data confirm that screening
mammography has a real but modest effect to decrease mortality from breast cancer and that effect
varies with age.” She points out that it is still debatable whether mammography screening is of value for
women under 50 years of age.
Nystrom, Lennarth, et al. Long-term effects of mammography screening: updated overview of the
Swedish randomized trials. The Lancet, Vol. 359, March 16, 2002, pp. 909-19
Gelmon, Karen A. and Olivotto, Ivo. The mammography screening debate: time to move on. The
Lancet, Vol. 359, March 16, 2002, pp. 904-05 (commentary)
Newspapers biased on mammography In 1993 the National Cancer Institute concluded that
there is insufficient evidence to recommend routine mammography screening for women aged 40 to 49
years. Other organizations have also questioned the benefits of screening in this age group. Yet despite
this evidence most newspaper articles on the topic still push screening. Researchers at the University of
Maryland reviewed 187 articles on mammography published in six American high-circulation newspapers
between 1990 and 1997. They found that mammography screening was recommended twice as often as
no screening for women aged 40 to 49 years. They conclude that newspapers tend to over-represent
support for screening in this age group and often do not provide the sources of their information and
recommendations.
Annals of Internal Medicine, Vol. 135, December 18, 2001
Mammography debate continues
COPENHAGEN, DENMARK. The prestigious Cochrane Institute has issued a review of the benefits of
breast cancer screening. This latest review is based on the conclusions reached by two Danish
researchers, Ole Olsen and Peter Gotzsche, in a previous study published in 2000. The review
concludes that there is no evidence that mass screening mammography reduces overall mortality among
women (www.cochranelibrary.net). Says Richard Horton, editor of The Lancet in commenting on the
study, “At present, there is no reliable evidence from large randomized trials to support screening
mammography programs.”
The Danish researchers also concluded that mass screening programs are associated with a 20 per cent
increase in mastectomies and a 30 per cent increase in overall surgery (www.thelancet.com). The
Cochrane Breast Cancer Group did not include this observation in the final review as they found it too
controversial.
It would appear that the support for mass screening (mammography) for breast cancer is waning. The
Cochrane review concludes, “The currently available reliable evidence does not show a survival benefit of
mass screening for breast cancer (and the evidence is inconclusive for breast cancer mortality). Women,
clinicians and policy makers should consider these findings carefully when they decide whether or not to
attend or support screening programs.” Editor’s Note: The fact that mass screening for breast
cancer is ineffectual does not mean that mammography cannot be a useful diagnostic tool if breast
cancer is suspected.
Olsen, Ole and Gotzsche, Peter C. Cochrane review on screening for breast cancer with mammography.
The Lancet, Vol. 358, October 20, 2001, pp. 1340-42 (research letter)
Horton, Richard. Screening mammography – an overview revisited. The Lancet, Vol. 358, October 20,
2001, pp. 1284-85 (commentary)
Mayor, Susan. Row over breast cancer screening shows that scientists bring “some subjectivity into their
work”. British Medical Journal, Vol. 323, October 27, 2001, p. 956
New breast cancer screening tool Researchers at Guy’s Hospital in London have developed
a camera so small that it can be inserted into one of the 15 or so holes in a woman’s nipple. Once inside
the milk duct it can scan for lumps or dull surfaces that may be indicative of a developing cancer.
New Scientist, October 27, 2001, p. 29
Breast cancer mortality and mammography
TORONTO, CANADA. Several clinical trials have observed a reduction in mortality from breast cancer in
women over 50 years of age who received regular mammograms. It is not known, however, whether this
benefit is greater than that obtained by an annual physical examination alone. Researchers at the
University of Toronto now report the results of a study designed to answer this question.
The clinical trial involved 39,405 women aged between 50 and 59 years at time of entry into the study
between 1980 and 1985. The women were randomized to receive either an annual mammogram (two-
view) and physical examination of the breasts or just physical examination alone. All participants were
taught and encouraged to practice self-examination as well.
By December 31, 1993 622 invasive and 71 in situ breast carcinomas had been discovered in the
mammography plus physical examination group and 610 invasive and 16 in situ cases had been
observed in the physical examination group only. Although the cancers tended to be discovered earlier in
the mammography group there was, after 13 years of follow-up, no difference in breast cancer mortality
between the two groups (107 deaths in the mammography group and 105 in the physical examination
group only).
The biopsy rates were considerably higher in the mammography group. In this group 24.3 per cent of the
participants underwent biopsy after the first screen as compared to 8.7 per cent in the physical
examination group. The researchers also noted a significant increase in deaths from pancreatic cancer in
the mammography group (42 deaths) as compared to the physical examination group (18 deaths).
Although this difference is statistically significant it could, according to the researchers, be due to
chance.
The researchers conclude that mammography screening does not result in a decrease in the absolute
rate of advanced breast cancer and does not reduce mortality when compared to physical examination
only. They suggest that physicians and their patients (women aged 50-59 years) consider the option of
an annual physical examination carried out by a health professional trained to recognize the signs of early
breast cancer plus regular self-examination as an alternative to annual mammograms. [43
references]
Miller, Anthony B., et al. Canadian National Breast Cancer Screening Study-2: 13-year results of a
randomized trial in women aged 50-59 years. Journal of the National Cancer Institute, Vol. 92,
September 20, 2000, pp. 1490-99
Older women may benefit from mammography
BOSTON, MASSACHUSETTS. Older women, that is women over 65 years of age, account for 48 per
cent of all newly diagnosed invasive breast cancers and 58 per cent of breast cancer deaths. Although
there have been many studies concerning the efficacy of mammography few, if any, have addressed the
question "Does it benefit women over 65 years?" Researchers at the Harvard Medical School have just
released the results of a study aimed at answering this question.
Their study involved almost 10,000 women aged 67 years or older who had been diagnosed with a first
primary breast cancer between 1987 and 1993. The researchers found that women who had never had a
mammogram were three times more likely to be diagnosed with advanced (stage II) breast cancer than
were women who had regular mammograms (at least two at least 10 months apart). Women who had
never had a mammogram were also three times (OR=3.38) more likely to die from breast cancer than
were women who had regular mammograms. The likelihood of being diagnosed with late stage (stage II
or higher) breast cancer, not surprisingly, increased with age with women over 85 who did not use
mammograms having a seven times greater risk than regular mammography users. The relative risk
between non-users and regular users in the 67 to 74 year age group was 2.46. The researchers noted
that 38 per cent of all deaths in this group of breast cancer patients was due to breast cancer. They
conclude that regular use of mammography will reduce the mortality and incidence of late stage breast
cancer among women aged 67 years and older.
McCarthy, Ellen P., et al. Mammography use, breast cancer stage at diagnosis, and survival among older
women. Journal of the American Geriatrics Society, Vol. 48, October 2000, pp. 1226-33
Mammography and hormone replacement therapy
MELBOURNE, AUSTRALIA. Many women over 50 years of age are prescribed hormone
replacement therapy (HRT) in order to ameliorate menopause symptoms and
prevent excessive loss of bone mass. Unfortunately, HRT has been associated
with an increased risk of breast cancer. It is therefore important that women
on HRT be checked for breast tumors at periodic intervals. Public health
authorities in most developed countries recommend screening with mammography
every one or two years for women over the age of 50 years. Australian
researchers now report that mammography is less accurate in women on HRT than
in women not on HRT. Their study involved 103,770 women in the state of
Victoria who had a mammogram for the first time in 1994. The use of HRT among
these women varied from 20.2 per cent in those aged 40-49 years to almost 40
per cent in women aged 50-59 years. The detected incidence of breast cancer
among women in the 50-59 year age group was 0.33 per cent (141 cases out of
43,090) for women not on HRT as compared to 0.58 per cent (100 cases out of
17,209) for women on HRT. Unfortunately, the sensitivity of the screening was
found to be significantly poorer in the case of women on HRT. In the age
group 50-69 years (the most vulnerable group) the sensitivity (percentage of
actual cancers detected) of mammography was only 64.3 per cent among HRT users
as compared to 79.8 per cent among non-users. So not only does HRT use
increase the risk of breast cancer, but it also makes it significantly harder
to detect. The researchers suggest that women on HRT may wish to discontinue
therapy for a brief period before mammography and also recommend that women be
told about the lack of accuracy of mammography in HRT users when they are
faced with the decision about whether to start HRT.
Kavanagh, Anne M., et al. Hormone replacement therapy and accuracy of
mammographic screening. The Lancet, Vol. 355, January 22, 2000, pp. 270-
74
Does mammography screening really save lives?
COPENHAGEN, DENMARK. Medical researchers at the Nordic Cochrane Centre have
reached the surprising conclusion that "screening for breast cancer with
mammography is unjustified". The researchers reviewed eight randomized trials
aimed at determining the effect of mammography screening on mortality from
breast cancer. The trials carried out in the United States, Canada, Scotland,
and Sweden involved over 500,000 women. A careful study of the design of the
trials showed that six of them were biased in a direction which would tend to
exaggerate the benefits of mammography. In some of the trials the women in
the screening group were significantly younger than those in the control
group. In others the screened women were in a significantly higher socio-
economic stratum than the women in the control group. The researchers
conclude that only two studies, the Canadian Mammography Screening Study and a
study carried out in Malmo, Sweden were sufficiently unbiased to be of value.
The pooled results of these studies showed no reduction in breast cancer
mortality due to the use of mammography screening. The researchers back up
their contention that mammography screening is unjustified by pointing out
that there has been no decrease in breast cancer mortality in Sweden since the
introduction of mammography in 1985.
The researchers conducted a more detailed analysis of the findings from the
Malmo and Stockholm trials and found that women in the mammography groups were
far more likely to have undergone surgery and radiotherapy than had women in
the control groups.
Dr. Harry J. de Koning of the National Evaluation Team for breast cancer
screening in the Netherlands comments on the Danish report in an accompanying
editorial. He believes there has been a reduction in breast cancer mortality
in the UK due, in part, to the national breast screening program. About
800,000 women are screened every year in the Netherlands, but no statistically
significant reduction in breast cancer mortality has been found in the first
nine years of the screening program. Dr. de Koning concludes that we still
need answers to the question "Are screening programmes justified and at what
cost to women and to society?"
Gotzsche, Peter C. and Olsen, Ole. Is screening for breast cancer with
mammography justifiable? The Lancet, Vol. 355, January 8, 2000, pp. 129-
34
de Koning, Harry J. Assessment of nationwide cancer-screening programmes.
The Lancet, Vol. 355, January 8, 2000, pp. 80-81 (commentary)
Mammography: A risky procedure?
ABERDEEN, SCOTLAND. Researchers at the University of Aberdeen warn that the
compressive force used in order to obtain useable mammograms may be a
contributing factor to breast cancer. The British standard for the force used
to squeeze the breast as flat as possible corresponds to placing twenty 1
kilogram bags of sugar on each breast. The researchers fear that this force
may be excessive and enough to dislocate and spread any existing cancer cells.
Animal experiments have shown that the number of cancer sites can increase by
as much as 80% when tumors are manipulated mechanically. A recent study in
Malmo, Sweden found that the death rate from breast cancer among women under
55 was 29% higher in a group which had been screened with mammography than in
the unscreened control group. The screening procedure used "as much
compression force as the women could tolerate".
The Lancet, July 11, 1992, p. 122
Canadian study questions the benefits of mammography
TORONTO, ONTARIO. The results of the Canadian National Breast Screening Study
are now in. This massive study involving almost 90,000 Canadian women aged 40
to 59 was carried out between 1980 and 1985 and provided for a seven-year
follow-up period. The researchers conclude that although annual mammograms
were found to be effective in detecting small, node-negative tumors at an
early stage there was no indication that regular mammography had any impact on
the rate of death from breast cancer within the 7 year follow-up period.
NOTE: This study has created a great deal of controversy and has been
vehemently condemned by many U.S. radiologists.
Canadian Medical Association Journal, November 15, 1992, pp. 1459-88
Vested interests attack Canadian mammography study
BOSTON, MASSACHUSETTS. The major, surprising finding of the Canadian National
Breast Screening Study was that there is no evidence that screening for breast
cancer with mammography is effective for women under 50 years of age. Not
surprisingly, this conclusion has been vehemently attacked by American
radiologists. Women in their 40s are the best customers for regular
mammograms. As many as 40% of them have an annual mammogram at a cost of $50-
100 each. Now another study in Sweden supports the Canadian findings. Dr.
Lazlo Tabar followed 35,000 women aged 40-49 for 11 years. He found no
evidence that regular mammographic screening of these women had any
benefits.
Gray, Charlotte. US resistance to Canadian mammogram study not only about
data. Canadian Medical Association Journal, Vol. 148, No. 4, February 15,
1993, pp. 622-23
Is mammography necessary at all?
BOMBAY, INDIA. Dr. Mittra of Tata Memorial Hospital in Bombay adds his voice
to the growing chorus of doctors and scientists questioning the value of
routine mammography screening. He believes that physical examination by
skilled practitioners is just as effective as mammography in detecting life-
threatening tumors. He also points out that the National Breast Screening
Study in Canada found no difference in mortality between women screened by
physical examination alone and women screened with physical examination plus
mammography. He estimates that the cost of mammography is 5-10 times higher
than the cost of physical examination. Dr. Mittra points out that mammography
may cause anxiety in women awaiting their test results and often leads to
unnecessary biopsies and treatments. He concludes that the question is not
"how to refine mammographic screening, but whether we need it at all".
Mittra, I. Breast screening: the case for physical examination without
mammography. The Lancet, Vol. 343, February 5, 1994, pp. 342-44
Breast cancer screening may cause more harm than good
VANCOUVER, CANADA. Women over 40 years of age have long been advised to have
an annual mammogram. Now questions are being raised within the medical
community about the wisdom of this advice. Two Canadian medical professors
conclude that the benefits of a general program of breast cancer screening are
marginal, that the potential for harm is substantial, and that the cost is
enormous. They estimate that only one in every 20,000 women screened actually
receive a benefit from the procedure; this converts into a cost of about $1.2
million for each life saved. The professors do not question the value of
mammography in the case of women who have signs of the disease, but consider
mass screening to be a waste of resources.
An Australian team from the University of Queensland echoes the conclusions of
the Canadians. They see little, if any, benefit in screening women under 50
years of age, but they do point out some of the serious negative effects -
later ill effects from the radiation they are exposed to during the mammogram,
the possibility that an existing tumor may spread due to the pressure exerted
on the breast during screening, and the anxiety caused by frequent false-
positive results. The Canadian researchers point out that a false-positive
result may not only produce great stress, but may also lead to unnecessary
biopsies and surgery. They also point out that mammography misses 10-15 per
cent of early breast cancers thus providing a false sense of security. Both
teams agree that mass screening of women under 50 years is of little benefit
and has the potential to cause a great deal of harm.
Glasziou, Paul P., et al. Mammographic screening trials for women aged under
50. The Medical Journal of Australia, Vol. 162, June 19, 1995, pp. 625-29
Wright, Charles J. and Mueller, C. Barber. Screening mammography and public
health policy: the need for perspective. The Lancet, Vol. 346, July 1, 1995,
pp. 29-32
False positives in mammography a serious problem
STOCKHOLM, SWEDEN. Swedish medical doctors report that erroneous diagnoses of
breast cancer in women screened with mammography is a serious and costly
problem. Their study involved a total of about 60,000 women aged 40 to 64
years who were screened for breast cancer. Of the 60,000 women screened, 726
were referred to the oncology department for follow-up because of the
detection of abnormal lesions. Additional tests confirmed that 224 of the
women did indeed have cancerous lesions while the remaining 502 (70 per cent)
were found to be cancer-free. The proportion of false positive results was
particularly high in women under 50 years; here more than 86 per cent of the
women referred for further testing turned out to be cancer-free. Of the women
who did have cancerous lesions 26 per cent were found to have ductal
carcinomas in situ, a form of breast cancer which is usually not considered
life-threatening. The researchers point out that false positive mammograms
can produce a high degree of anxiety in the women concerned. The follow-up
testing is also very expensive and often lengthy; in the present study follow-
up of false positive results accounted for almost a third of the cost of the
entire screening programs. The authors conclude that the benefits of
mammography in women under 50 years must be carefully weighed against the
potentially negative aspects.
Lidbrink, E., et al. Neglected aspects of false positive findings of
mammography in breast cancer screening: analysis of false positive cases from
the Stockholm trial. British Medical Journal, Vol. 312, February 3, 1996, pp.
273-76
Breast cancer overdiagnosed and overtreated
SAN FRANCISCO, CALIFORNIA. Ductal carcinoma in situ (DCIS) of the breast is a
fairly common non-invasive form of breast cancer. Most cases of DCIS are
detected through the use of mammography. It is estimated that DCIS accounts
for about 30 to 40 per cent of all mammographically detected breast cancers
and constitutes about 12 per cent of all diagnosed breast cancers in the
United States. Almost all cases of DCIS are treated with some form of
disfiguring surgery - this despite the fact that it is unknown whether the
detection and treatment of DCIS actually extend the lives of the patients.
The number of detected and surgically treated DCISs has risen astronomically
since the introduction of screening mammography. Between 1973 and 1983 the
age-adjusted rate for DCIS rose by 53 per cent in the United States.
Following the introduction of mammographic screening in 1983, the incidence of
DCIS increased by 328 per cent in the period between 1983 and 1992. It is
estimated that at least 200 per cent of this 328 per cent increase is due to
the use of mammography. The increase in diagnosed DCIS has been particularly
high in women under 50 years of age where the growth in annual incidence rate
was about 4,000 per cent greater for the period 1983-1992 than for the period
1973-1983.
In 1992, about 44 per cent of all cases of DCIS were treated with mastectomy
(removal of entire breast), 23 per cent were treated with lumpectomy (removal
of affected area only) plus radiation, 30 per cent were treated with
lumpectomy alone, and about 3 per cent were not surgically treated at all.
Survival rates during the first one to nine years were generally 100 per cent
irrespective of type of treatment. The use of mastectomy was found to vary
widely by geographical area from 28.8 per cent in Connecticut to almost 60 per
cent in New Mexico. The authors of the recent report from the University of
California express serious concerns about the increasing number of DCIS cases
being detected through screening mammography especially since almost all of
these cases are treated with disfiguring surgery. The concern is particularly
acute in the case of younger women (30 to 39 years of age) where 92 per cent
of all cancers detected by mammography are classified as DCIS. The authors
conclude that there is an urgent need to study the appropriateness of the
various treatment options from mastectomy to watchful waiting.
Ernster, Virginia L., et al. Incidence of and treatment for ductal carcinoma
in situ of the breast. Journal of the American Medical Association, Vol. 275,
No. 12, March 27, 1996, pp. 913-18
Page, David L. and Jensen, Roy A. Ductal carcinoma in situ of the breast.
Journal of the American Medical Association, Vol. 275, No. 12, March 27, 1996,
pp. 948-49
More tests lead to more surgery
PORTLAND, MAINE. Physicians have long been puzzled why some areas of the New
England states have very high rates of heart surgery while others have
relatively low rates. Now researchers at the Maine Medical Center report that
the amount of heart surgery (bypass surgery and angioplasty) done in an area
is almost entirely dependent upon how much diagnostic testing is done in that
area. In other words, it bears little or no relation to the actual prevalence
of heart disease. The researchers found a strong linear relationship between
the number of stress tests done in a certain geographical area and the number
of subsequent angiography examinations and surgical interventions. This
relationship could only be explained by concluding that more testing leads to
more surgery. Other New England researchers have arrived at a similar
conclusion and have also discovered that more mammography leads to more
biopsies and more breast surgery, that more spine x-rays lead to more back
surgery, and that more prostate biopsies and most likely more PSA tests lead
to more radical prostatectomies. The researchers conclude that "how much
disease is diagnosed depends on how hard one looks." They also suggest that
physicians should recognize that just as more therapy may be harmful so may
more diagnostic tests. The total Medicare billings by American physicians in
1993 for diagnosis and treatment of coronary heart disease exceeded one
billion dollars. Medical researchers estimate that 80 per cent of all
angiographic procedures are inappropriate and that half of all bypass
operations performed in the United States are unneccessary or of no
benefit.
Wennberg, David E., et al. The association between local diagnostic testing
intensity and invasive cardiac procedures. Journal of the American Medical
Association, Vol. 275, No. 15, April 17, 1996, pp. 1161-64
Verrilli, Diana and Welch, H. Gilbert. The impact of diagnostic testing on
therapeutic interventions. Journal of the American Medical Association, Vol.
275, No. 15, April 17, 1996, pp. 1189-91
Mammography screening not recommended for women under 50
SAN DIEGO, CALIFORNIA. The American College of Preventive Medicine has joined
the American College of Physicians and the American Academy of Family
Physicians in recommending routine annual or biannual mammography screening
for women aged 50 to 69 years. The College does not recommend screening for
women under 50 years as there is no evidence that this practice is useful.
The proportion of false positives is high when screening younger women and
there have even been suggestions that early screening may increase mortality.
The Canadian Task Force on Periodic Health Examination specifically recommends
against mammography screening of women aged 40-49, but does support routine
annual screening for women aged 50-69. The American College of Preventive
Medicine recommends further research to clarify the risk/benefit ratio of
mammography screening in women under 50 years of age and also suggests that
menopausal status rather than age may be a better indicator of when screening
should begin.
Ferrini, Rebecca, et al. Screening mammography for breast cancer: American
College of Preventive Medicine practice policy statement. American Journal of
Preventive Medicine, Vol. 12, No. 5, September/October 1996, pp. 340-41
New, simple test for breast cancer developed in Japan
FUKUOKA, JAPAN. Medical researchers at the Kyushu University report the
development of a new, simple test for breast cancer which is non-invasive,
avoids exposure to radiation, and is exceptionally accurate. The new test
involves placing an absorbent pad on the nipple and leaving it there for 24
hours to absorb the normal secretions from the area. The contents of the pad
are then analyzed for the presence of carcinoembryonic antigen (CEA) using an
enzyme immunoassay technique. The researchers' initial study of the new test
involved 22 healthy women without any signs of breast cancer and 32 women with
confirmed breast cancer. The CEA content in the pads from the healthy women
averaged 0.6 units from each nipple. The amount of secretion was found to be
unrelated to the menstrual cycle. The CEA content in the pads from women with
breast cancer was much higher; an average of 16.1 units in the cancerous
breast and 2.0 units in the non-cancerous breast. The test successfully
confirmed the presence of cancer in 30 of the 32 women giving a rate of false-
negative results of 6 per cent. The incidence of false-positive results was 0
per cent. The location of the densest stains (heaviest secretion) on the
absorbent pad was found to be closely related to the location of the actual
breast tumor. Heavy staining on the upper or lower, and outer and inner part
of the pad was found to correspond with tumor locations in the upper, lower or
outer or inner part of the breast as confirmed upon removal of the tumor. The
researchers speculate that each CEA stain on the absorbent pad corresponds to
the excretory ducts of the mammary glands that open into the nipple.
Imayama, Shuhei, et al. Presence of elevated carcinoembryonic antigen on
absorbent disks applied to nipple area of breast carcinoma patients. Cancer,
Vol. 78, No. 6, September 15, 1996, pp. 1229-34
Temperature sensitive pads detect breast cancer
CRANFORD, NEW JERSEY. An American engineer, Zsigmond Sagi, has developed a
temperature sensitive pad which can be used to detect breast cancer in its
early stages. The soft, lightweight pads are worn inside the bra for 15
minutes and are then visually analyzed for telltale signs of temperature
variations. The pads record the skin temperatures across three large areas of
each breast. If an area of one breast shows a temperature 2oF or more higher
than the corresponding area of the other breast there is a high probability
that a cancerous tumor is present. Clinical trials of the pads carried out
prior to FDA approval found that they were accurate in predicting breast
cancer in 80 per cent of all women and in 90 per cent of women under 50 years
of age. The pad technology is particularly valuable for younger women where
mammography is not very accurate and is far safer and more comfortable than
mammography. The technique is, however, not suitable for women who have had a
mastectomy or lumpectomy or whose breasts are mismatched for other reasons.
The presence of mastitis or sclerosing adenosis can provide false postive
readings due to the heat generated by inflammation. A large clinical trial of
the pads involving almost 6,000 women is currently underway. This trial will
compare the pad results with the results of biopsies and the participants will
be followed-up for four years. NOTE: The pads, BreastAlert Differential
Temperature Sensor, are available to physicians from Humascan Inc., Cranford,
NJ and cost $25/pair.
Heat-seeking pads may help find early breast cancers. Journal of the National
Cancer Institute, Vol. 89, October 1, 1997, pp. 1402-04
Energy medicine device detects breast cancer
LONDON, UNITED KINGDOM. The initial diagnosis of breast cancer is usually
made during a physical examination or from a mammogram. The majority of the
lesions or masses discovered will turn out to be benign. However, to
establish this fact the women involved have to go through additional
diagnostic tests such as further mammography, ultrasound, fine needle
aspiration or open surgical biopsy. These additional tests are expensive and
anxiety-provoking. Now a team of researchers from eight European hospitals
and universities reports that an energy medicine device, the Biofield
Diagnostic System, can provide accurate information as to whether an abnormal
breast mass is cancerous or not. The study involved 661 women with suspicious
lesions who had been scheduled for surgical biopsy. Prior to the biopsy the
women were tested on the Biofield device. The test involves placing
electrodes (similar to those used in obtaining electrocardiograms) on the skin
over the suspicious breast mass as well as around the mass and in an identical
pattern on the unaffected breast. Reference electrodes are placed on the
palms of the hands. Electropotential (voltage) measurements are made over a
one-minute period and recorded. The researchers found a very strong
correlation between the magnitude of the differences in electropotential
between the involved and uninvolved breasts and the likelihood that the
suspicious lesion would be cancerous (as determined by the subsequent biopsy).
The researchers conclude that the Biofield test can be used to reliably rule
out malignant disease with a negative predictive value as high as 99.1 per
cent. The accuracy of the test is somewhat less with non-palpable lesions
because of the difficulty in placing the sensors accurately. NOTE: This study
was partly funded by Biofield Corp., the manufacturer of the device.
Cuzick, Jack, et al. Electropotential measurements as a new diagnostic
modality for breast cancer. The Lancet, Vol. 352, August 1, 1998, pp. 359-
63
Breast cancer screening made easy
SYDNEY, AUSTRALIA. A team of Australian, American, and Japanese researchers
report the development of a new, highly-accurate test for breast cancer. The
test uses a single scalp or pubic hair and was found to be 100 per cent
accurate in predicting the presence of breast cancer. The hair sample is
examined by X-ray diffraction using synchrotron radiation. Hair samples from
breast cancer patients exhibit a characteristic change in their X-ray
scattering patterns. In one trial, 23 out of 23 hair samples from breast
cancer patients showed the characteristic pattern while only four out of 28
samples from healthy women had an abnormal scattering pattern. The test was
also found to be useful in identifying women who were at greater risk of
developing breast cancer either because of the presence of a genetic mutation
or because of a family history of breast cancer. The researchers recommend
further research into the sensitivity and specificity of the new test and
conclude that this may lead to a simple and reliable screening method for
breast cancer using a single hair.
James, Veronica, et al. Using hair to screen for breast cancer. Nature, Vol.
398, March 4, 1999, pp. 33-4 (scientific correspondence)
New, painless test for breast cancer
NEWCASTLE, AUSTRALIA. X-ray mammography is widely used to screen women for
breast cancer. Unfortunately, mammography is not very accurate and can
produce a significant number of false positives (no cancer present) and false
negatives (cancer present, but not detected). The test can be very painful
due to the compression of the breast necessary for clear pictures and there is
some evidence that this compression can actually promote or spread existing
cancer. There are several alternative screening tests available, but none
have been able to dislodge x-ray mammography from its preeminent position.
Medical researchers at the John Hunter Hospital in Australia now suggest that
scintimammography may be superior to x-ray mammography in many ways.
Scintimammography makes use of a radioactive tracer (Technetium-99m) which is
injected into a vein followed by examination of the breasts by a gamma camera.
The new test can be done using standard equipment available in any nuclear
medicine department. The researchers examined 115 women scheduled for breast
cancer surgery using x-ray mammography, scintimammography, and ultrasound
examination and fine needle biopsy where appropriate. Of the 96 confirmed
cancer cases scintimammography correctly identified 81 whereas standard
mammography identified only 61. Similarly, while scintimammography failed to
detect 15 existing cancers x-ray mammography failed to detect 31 cases. X-ray
mammography also indicated that six out of 19 non-cancerous women had cancer
while the number of false positives with scintimammography was only three out
of 19. Scintimammography was found to be vastly superior to x-ray mammography
in detecting cancer in patients who had had previous breast surgery or
radiation treatments. The researchers conclude that scintimammography has the
potential to prevent unnecessary breast biopsies and offers additional
advantages in patients who have already undergone treatment for breast
cancer.
Howarth, Douglas, et al. Scintimammography: an adjunctive test for the
detection of breast cancer. Medical Journal of Australia, Vol. 170, June 21,
1999, pp. 588-91
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